Here is the situation:

I left on Maternity leave the first week of January. I had been in my present position 7 months. My maternity leave was never truly discussed regarding length, etc.

Last Friday was my 6 week check-up. During my visit some other health issues came to light along with Post partum depression. My doctor stated I needed to have additional testing done and she wanted me off another 2 weeks.

I notified my employer by email because it was past 4:30 and there was nobody left in the office. I also notified the HR manager via phone as she is a close friend. I was already scheduled to be off Monday 2/20 for some hearing tests. At 3:30 Monday afternoon, the HR manager calls me and tells me not to return. I assumed she meant on Tuesday. No, the general manager had eliminated my job from the company entirely. I never did receive acknowledgment of the email from the general manager, however the HR manager confirmed he did get it.

Then, I found out the general manager has a meeting with the board. Right before my leave he was instructed to cut some corners because payroll was so high. This meeting tomorrow would be the subsequent meeting to that one. I am left to believe that I was cut today to make him look good tomorrow.

is any part of what they did legal? Do I have any type of recourse?

You had worked for the company for less than one year, so you were not eligible for leave under the Family and Medical Leave Act (FMLA) that would have provided you with job protection for 12 weeks' leave. Thus, the employer's obligation at this point is to not treat you any differently than it would any other employee who had a non-maternity health issue that caused him/her to be absent.

Your doctor does not have the legal right to "take you off work" unless FMLA is involved. The doctor does not run your employer's business.

Nor does having been on maternity leave protect you from an action that would have been taken regardless of your leave.

For this to be illegal, you are going to have to present evidence that another employee who is not eligible for FMLA and who has missed six weeks of work for a non-maternity condition and who requested another two weeks off would not have been fired, AND that you would not have been the person who was let go for financial reasons if you had not taken maternity leave.